lecture 31: diseases and disorders 3: uterine Flashcards
What is gynaecology?
- gynaecology is a medical speciality focued on women’s health, in particular the genital tract in non-pregnant women (ovaries, uterus, vagina)
- a gynaecologist manages medical and surgical problems affecting women’s reproductive and urological systems
- problems with menstruation
- lower abdominal pain
- gynaecologic malignancies
- fertility problems
- sexual health
- sexually transmitted diseases
- urinary incontinence
What is the human menstrual cycle?

What are normal limits for menstrual bleeding?
- frequency of menses (days)
- frequent: less than 24
- normal: 24-38
- infrequent: more than 38
- regularity of menses: cycle-to-cycle variation over 12 months, days
- absent: no bleeding
- regular: variation ± 2-20
- irregular: variation more than 20
- duration of flow, days
- prolonged: more than 8.0
- normal: 4.5 - 8.0
- shortened: less than 4.5
- volume of monthly blood loss, mL
- heavy: more than 80
- normal: 5 - 80
- light: less than 5
- abnormal uterine bleeding (AUB) occurs when menstrual uterine bleeding falls outside normal parameters
- unscheduled bleeding between menstrual cycles is also categorised as abnormal
What is PALM-COEIN?
- classification system for causes of abnormal uterine bleeding in the reproductive years
- women may fit into more than one category
- Polyps
- Adenomyosis
- Leiomyoma (uterine fibroids)
- Malignancy and hyperplasia
- Coagulopathy (clotting disorders e.g. von Willebrand disease)
- Ovulatory disorders
- Endometrium
- Iatrogenic (non-menstrual bleeding or spotting due to hormonal therapies)
- Not classified

What is Heavy Menstrual Bleeding (HMB)?
- Menorrhagia definition: excessive menstrual blood loss which interferes with the woman’s physical, emotional, social and material quality of life
- normal average monthly menstrual blood loss (MBL) = 35 mL
- HMB usually defined as MBL more than 80ml (=90th per centile)
- HMB: increased incidence of iron deficiency and anaemia
- incidence:
- affects 10-30% of menstruating women
- increases up to 50% peri-menopause
- costs:
- social, medical and public health issue
- economic implications (e.g. treatment costs, lost work days)
What are treatments for HMB?
- treatment depends on cause and life stage of the women
- medical:
- hormonal:
- combined oral contraceptive pill
- progestogens e.g.: Mirena - intrauterine device that releases Levonorgestrol
- prostaglandin synthetase inhibitors (e.g. megenamic acid)
- block prostaglandin production (prostaglandins have roles in inflammation, vessel function, platelet aggregation etc)
- anti-fibrinolytic agents (e.g. Tranexamic acid)
- fribrinolysis: process that dissolves fibrin resulting in removal of small blood clots
- hormonal:
- surgical:
- endometrial ablation: removal of lining of uterus
- hysterectomy: surgical removal of the uterus
- management of iron deficiency
Why is HMB research difficult?
- limited research - no animal models
- observation studies using human tissue samples
- basic studies on mechanisms of mesntruation
- clinical trials comparing treatments
- NHMRC Funding Research Project: Mechansisms of Heavy Menstrual Bleeding (Hickey, Rogers and Girling)
- Aim: understand the molecular mechanisms playing a role in HMB associated with common clinical presentations:
- regular menstrual cycles with/without uterine fibroids
- Aim: understand the molecular mechanisms playing a role in HMB associated with common clinical presentations:
- investigate pathways already known to have a role in HMB
- identify novel pathways involved in HMB
What are uterine fibroids?
- Leiomyoma: benign clonal tumours of the smooth muscle cells of the uterine muscle wall (myometrium)
- incidence:
- most common benign tumour in fertile women
- affect around one third of women aged 18-30 years and 50-80% of women by age 50
- incidence and severity is higher in women of african descent
- main indication for hysterectomy
- key symptoms
- not all fibroids are symptomatic
- heavy menstrual bleeding
- pain symptoms
- fertility and pregnancy problems
- costs
- negative effects on quality of life
- high personal and healthcare costs
What are features of fibroids?
- fibroids are heterogeneous
- firm, round outline well demarcated from surrounding myometrium
- single or multiple
- vary in size
- variable in location:
- submucosal
- intramural
- subserosal
- pedunculated
- bundles of differentiated smooth muscle cells (SMC), fibrous tissue, sparse vasculature, few mitotic figures

Images of fibroids

What are symptoms of uterine fibroids?
- approximately 25% of women with fibroids have clinical symptoms
- incidence and severity of symptoms depends on size, number and location of fibroid
- distortion of uterine cavity or surface
- irregular or excessive/heavy menstrual bleeding (which may be associated with anaemia)
- pelvic pain or pressure
- bowel and bladder dysfunction
- fertility problems
- recurrent miscarriage
What are non-surgical treatments of uterine fibroids?
- treatments tailored to individual patient based on severity of symptoms, and age and proximity to menopause
- is fertility preservation required?
- side effects
- medical treatments:
- GnRH analogues: may be used to induce hypoestrogenic state to shrink tumours before surgery
- short term use only
- effects on fibroid growth temporary
- side effects
- progestins (e.g. mirena): to reduce HMB
- hormone modulators e.g. SERM, SPRMS
- GnRH analogues: may be used to induce hypoestrogenic state to shrink tumours before surgery
What are surgical interventions used to treat uterine fibroids?
- hysterectomy: removal of uterus
- myomectomy: removal of uterine fibroid
- uterine artery embolization: delivery of particulate material through the uterine arteries to block the blood supply to vessels of the uterine fibroid
- magnetic resonance-guidance focused-ultrasound (MRgFUS): application of high-intensity focused ultrasound energy to locally heat and destroy diseased or damaged tissue through ablation
- leads to thermal destruction of fibroid
- only suitable for certain types of fibroid

What are fundamental factors involved in myometrial physiology and uterine leiomyoma formation and growth?
- genetic factors:
- chromosomes 2, 3, 6, 7, 8, 10, 11, 12, 13, 14, 22
- genes - MED12, HMGA2, HMGA1, FH, BHD, TSC2, PCOLCE, ORC5L and LHFPL3
- risk factors:
- early menarche
- age (late reproductive years)
- heredity
- nulliparity
- obesity
- PCOS
- diabetes
- hypertension
- cytokines
- IL1, 6, 11, 13, 15
- TNFalpha
- GM-CSF
- erythropoietin
- epigenetic factors:
- DNA methylation, histone modifciation, miRNA (let7, miR-21, miR-93, miR-106b, and miR-200)
- ECM components:
- collagen, fibronectin and proteoglycans
- chemokines:
- MIP1alpha, MIP-1beta
- RANTES
- eotaxin, eotaxin-2
- IL-8
- CCR1, CCR3, CCR5
- CXCR1, CXCR2
- MCP-1
- growth factors
- EGF, HB-EGF, PDGF, IGF, TGF-alpha, TGF-beta, VEGF, aFGF, bFGF
- activin and myostatin
- progesterone
- oestrogen

What is research on uterine fibroids?
- despite scale of problem - limited research
- heterogeneity not necessarily recognised in study design
- lack of suitable animal models
- observational studies:
- comparing fibroid and host myometrium, regressing and growing fibroids for expression of growth factors, receptors etc
- in vitro studies:
- using cultured fibroid and host myometrial SMCs for examining interactions between ER, PR and growth factors etc
- But! cultured cells may not be representative of what goes on in vivo
- examples of our research:
- retinoid pathway: Zaitseva et al
- differential gene and protein expression - contribution to mechanisms? Zaitseva et al
- fibroid heterogeneity: zhao and rogers, tsiligiannis
- using MRgFUS to investigate how symptomatic fibroids cause heavy menstrual bleeding

What is endometriosis?
- presence of oestrogen-dependent endometrial lesions containing glands and stroma outside of the uterus
- incidence
- 6-10% of reproductive-aged women
- 50-60% of women with pelvic pain
- 30-50% of women with infertility
- key symptoms
- various pain symptoms
- fertility problems
- costs
- negative effects on quality of life: mental, social and physical wellbeing
- high personal and healthcare costs

What are common locations for endometriosis?
- endometrial implants/lesions
- endometrial nodules
- endometriomas
- umbilicus
- coecum
- peritoneum
- appendix
- bladder
- uterine serosa
- uterovesical fold
- rectovaginal septum and uterosaccral ligaments
- sigmoid colon
- ovary
- ureter
- fallopian tube
- small bowel

What are the symptoms of endometriosis?
- complicated range of pain symptoms - symptoms can overlap with other disorders
- women may be asymptomatic or symptomatic
- key symptoms: pain, infertility and/or HMB
- pain symptoms include (but not limited to):
- dysmenorrhea (menstrual period pain)
- pyspareunia (pain during sexual intercourse)
- non-menstrual pelvic pain
- lower back pain
- ovulation pain
- bowel and bladder symptoms
- fatigue
- fertility problems
- women with endometriosis are at increased risk of autoimmune disease, ovarian cancer (endometriod and clear-cell), and other cancers (e.g. non-Hodgkin’s lymphoma, melanoma)
How is endometriosis diagnosed?
- often a delay from onset of symptoms until diagnosis of endometriosis. Research suggests a mean delay of 6.7 years
- definitive diagnosis requires surgery (laparoscopy) to visualise the lesions

How can endometriosis be treated?
- multi-disciplinary: surgical, medical, and management approaches (e.g. psychology, physiotherapy)
- surgery:
- removal of lesions and adhesions - often by laparoscopy
- sometimes hysterectomy
- medical:
- manipulation of hormones to produce a pseudo-pregnant or pseudo-menopausal state (amenorrhea)
- androgens e.g. danazol
- GnRH antagonists e.g. zoladex
- progestogens e.g. Mirena
- combined oral contraceptives
- manipulation of hormones to produce a pseudo-pregnant or pseudo-menopausal state (amenorrhea)
- pain relief: analgesics, NSAIDs
- side effects have to be considered
- symptoms often recur after treatment
What are theories about the aetiology of endometriosis?
- no one theory can explain all aspects of the pathology
- mesothelium, other cell types → metaplasia
- mullerian rests → induction
- E2
- environment
- inflammation
- genetics
- lymphatic spread, haematogenous spread
- bone marrow
- mesenchymal
- haematopoietic stem cells
- endothelial precursors
- endometrial tissue and cell reflux
Do implants arise from uterine endometrium?
- retrograde menstruation theory: explains physical displacement of endometrial fragments into the peritoneal cavity, but not the development of lesions
- retrograde menstruation occurs in 90% of women, but endometriosis only develops in 10%
- also need:
- escape from immune clearance
- attachment to peritoneal epithelium
- invasion of the epithelium
- establishment of blood vessels and innervation
- continued growth and survival
Do implants arise from tissues other than uterus?
- coelomic metaplasia: transformation of normal peritoneal tissue to endometrial tissue
- induction theory: an endogenous stimulus, such as hormone, promotes differentiation of cells in the peritoneal lining to endometrial cells
- embryonic mullerian rests: cells residual from embryologic mullerian duct migration maintain the capacity to develop into endometriotic lesions under the influence of oestrogen
- extrauterine stem or progenitor cells from bone marrow may differentiate into endometriotic tissue
- benign metastasis: lesions result from lymphatic or haematogenous (via blood) transport of endometrial cells
What are features of the pathophysiology of endometriosis?
- genetics vs environment
- hereditable component to endometriosis
- risk for first-degree relatives of women with severe endometriosis is 6 times higher than relatives of unaffected women
- increased endometrial cell survival
- acquired genetic alterations – endometrial cells have high turnover and are therefore vulnerable to genetic recombination errors
- altered hormonal activity
- oestrogen (E) dependence
- localised E production by lesions
- progesterone (P) resistance - deregulated activity of P in lesions and uterus
- dysregulation of immune clearance and refluxed endometrial cells
- endometrial cell invasion and attachment
- shares features with malignancy
- matrix metalloproteinase activity
- angiogenesis and neuroangiogenesis
- growth of blood vessels into lesions
- growth of nerve fibres/axons into lesions
- inflammation
- increased number of activated macrophages in women with endometriosis
- altered cytokine/chemokine profile
- increased prostaglandins in peritoneum
What are endometriosis research directions?
- epidemiology
- environment
- BMI
- diet
- genetic studies
- diagnosis
- biomarkers
- imaging
- classification and prognosis
- clinical staging
- phenotype symptoms
- clinical trials, treatment and outcomes
- multi-centre RCTs
- defined outcome measures
- pelvic pain
- novel medical treatments
- pathophysiology
- immunomodulators
- inflammatory mediators
- macrophage
- oxidative stress
- pain
- angiogenesis
- lymphangiogenesis
- stem cells
- apoptosis
- miRNA
- animal and in vitro models
- transgenic models
- progestins and SPRMs
- ovary
- microbiome
- research policy
- data regestries and Biobanks
- centres of expertise
- multidisciplinary approaches
- lobbying
- national endometriosis organisations
- WES and WERF
What is their research into genetics and endometriosis?
- large genome-wide association studies (GWAS) have been conducted by various international groups including collaborators at the queensland institute of medical research
- uno et al
- painter et al
- nyholt et al
- GWAS is a very powerful approach to discover genes influencing risk for endometriosis
- the studies have identified several association loci (i.e. loci linked with endometriosis risk) and potential candidate endometriosis genes
- next step: how do we use results from the GWAS studies to identify disease mechanisms and drugable targets?
What is their research into nerve fibres and pain in endometriosis?
- there is relatively little fundamental or applied research aimed at understanding endometriosis associated pain
- aims:
- to determine whether aberrant innervation is present in the uteri of women with endometriosis, or more broadly in women with pelvic pain
- nerve fibre distribution, density and phenotype in women with different pathologies and pain symptoms
- to investigate how endometriotic lesions alter the interaction of neurons with the central nervous system
- mechanistic studies investigating how endometriotic lesions affect the cell bodies in the dorsal root ganglia
- to determine whether aberrant innervation is present in the uteri of women with endometriosis, or more broadly in women with pelvic pain
What are the key points?
- HMB occurs in 10-30% of women
- multiple causes
- mechanisms responsible for HMB are not understood
- uterine fibroids are common benign tumours of the uterine muscle wall
- heterogeneous tumours - size, shape, location, molecular and histological characteristics
- aetiology unknown
- endometriosis is a common gynacological disorder causing pain and fertility problems
- presence of endometrial tissue outside of the endometrium
- delay until definitive diagnosis, which requires laparoscopy
- variable treatments, but disease commonly recurs